Question

Eighteen middle-aged women with platelet readings between 120,000 platelets per microliter and 150,000 platelets per microliter of blood were selected randomly from the population of similar female patients at a large local hospital. Nine of the 18 women were assigned randomly to group A and received a placebo. The other nine women were assigned to group B and received a new platelet drug. After four months, posttreatment platelet readings were taken for all 18 women and were compared with pretreatment readings. The reduction in platelet level (Pretreatment reading - Posttreatment reading) for each woman in the study is shown here. Group (placebo) increase (in platelets per microliter): 2,000, 5,000, 7,050, 10,125, 12,345, 17,350, 13,250, 12,200,9,125 Group B (platelet drug) increase (platelets per microliter): 28,450, 23,438, 36,380, 12,450, 16,100,21,350, 39,400, 41,000, 14,325 Part A: Do the data provide convincing evidence, at the a = 0.05 level, that the platelet drug is effective in producing a reduction in mean platelet level? (6 points) Part B: Create and interpret a 95% confidence interval for the difference in the placebo and the new drug (4 points) (10 points)

i just need part b

Answer 1

We have

Difference of means (part A-partB)=Xd=-16049

Standard deviation=12027.37

For 95%confidence interval

Alpha=0.05

CRITICAL value=2.306

95%confidence interval=(Xd±critical value*sd/√n)

=(-16049±2.306*12027.37/√9)

=(-25294.0384,-6803.9616)(ans)

Thanks!

Stay safe!